The Kangaroos are in London to prepare for their rugby league world cup semi-final with Fiji this weekend at Wembley with the fitness of Billy Slater the main concern for coach Tim Sheens.

Kangaroos star Jarryd Hayne has launched a passionate defence of the Rugby League World Cup against detractors who claim the tournament is a waste of time.

Rugby league's international showpiece has come under fire from some quarters due to its lopsided scorelines and small crowds but Hayne says the end-of-season showpiece is vital in helping to grow the game.

Australia's 62-0 win over USA in the quarter-finals before 5762 fans in Wrexham, Wales has been pointed to by critics as indicative of what is wrong with the tournament.

Jarryd Hayne goes over for a try past US player Joseph Paulo.Source: AP

But Hayne said things needed to be put into perspective, and pointed to the Fijian Rugby League's new three-year $F4 million ($A2.35 million) sponsorship deal with Vodafone Fiji as evidence of that.

"5 years ago not many people new about rugby league in Fiji. The World Cup kick started the interest for rugby league in fiji. The World Cup changed the culture of rugby league in Fiji. A sport that was played very little is now just received 4million in funding," Hayne wrote on his Instagram account.

The crowd for Australia's quarter-final was a record, as was the 5021 who turned up for their 50-0 win over Ireland in their final group match at Thomond Park, Limerick.

And Hayne said the tournament, which hosts a semi-final doubleheader at Wembley Stadium this weekend with Fiji playing Australia and England meeting New Zealand, had done plenty to promote the game away from its heartlands in Australia and England. "Waste of time some are saying!! What's the point some are saying," wrote Hayne who played four games for Fiji at the 2008 World Cup.

Jarryd Hayne in action for Fiji at the 2008 Rugby League World Cup.Source: News Limited

"To those knuckle heads. His a life lesson. You Gota take small steps be4 u take big 1's. Fiji did that in 08 with the help of some great people who worked there backsides of in seeing the game grow, have now be rewarded with much needed funding. Congrats to Peni, #vodafone and all the Bati staff who got the deal dun. hopefully in 4-5 years time another country can celebrate a deal like this as well #RLWC2013 #MoreThanAGame."

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